Method and apparatus to facilitate support for multi-radio coexistence

ABSTRACT

A method of wireless communication by user equipment (UE) identifies a coexistence issue corresponding to a set of communication resources of the UE. The UE transmits, to a base station, an indication of the coexistence issue. The UE receives, from the base station, a communication parameter for selectively scheduling a measurement gap pattern. The UE communicates in accordance with the measurement gap pattern to mitigate the coexistence issue.

CROSS-REFERENCE TO RELATED APPLICATIONS

The present application is a divisional of U.S. patent application Ser.No. 12/904,509, filed on Oct. 14, 2010, and entitled “METHOD ANDAPPARATUS TO FACILITATE SUPPORT FOR MULTI-RADIO COEXISTENCE,” whichclaims the benefit of U.S. Provisional Patent Application No.61/319,324, filed on Mar. 31, 2010, and entitled “METHOD AND APPARATUSFOR MITIGATING COEXISTENCE PROBLEMS VIA UE INTERACTION WITH ENB,” U.S.Provisional Patent Application No. 61/356,973, filed on Jun. 21, 2010,and entitled “METHOD AND APPARATUS TO FACILITATE SUPPORT FOR MULTI-RADIOCOEXISTENCE,” and U.S. Provisional Patent Application No. 61/389,637,filed on Oct. 4, 2010, and entitled “METHOD AND APPARATUS TO FACILITATESUPPORT FOR MULTI-RADIO COEXISTENCE, the disclosures of which areexpressly incorporated by reference herein in their entireties.

TECHNICAL FIELD

The present description is related, generally, to multi-radio techniquesand, more specifically, to coexistence techniques for multi-radiodevices.

BACKGROUND

Wireless communication systems are widely deployed to provide varioustypes of communication content such as voice, data, and so on. Thesesystems may be multiple-access systems capable of supportingcommunication with multiple users by sharing the available systemresources (e.g., bandwidth and transmit power). Examples of suchmultiple access systems include code division multiple access (CDMA)systems, time division multiple access (TDMA) systems, frequencydivision multiple access (FDMA) systems, 3GPP Long Term Evolution (LTE)systems, and orthogonal frequency division multiple access (OFDMA)systems.

Generally, a wireless multiple-access communication system cansimultaneously support communication for multiple wireless terminals.Each terminal communicates with one or more base stations viatransmissions on the forward and reverse links. The forward link (ordownlink) refers to the communication link from the base stations to theterminals, and the reverse link (or uplink) refers to the communicationlink from the terminals to the base stations. This communication linkmay be established via a single-in-single-out, multiple-in-single-out,or a multiple-in-multiple out (MIMO) system.

Some conventional advanced devices include multiple radios fortransmitting/receiving using different Radio Access Technologies (RATs).Examples of RATs include, e.g., Universal Mobile TelecommunicationsSystem (UMTS), Global System for Mobile Communications (GSM), cdma2000,WiMAX, WLAN (e.g., WiFi), Bluetooth, LTE, and the like.

An example mobile device includes an LTE User Equipment (UE), such as afourth generation (4G) mobile phone. Such 4G phone may include variousradios to provide a variety of functions for the user. For purposes ofthis example, the 4G phone includes an LTE radio for voice and data, anIEEE 802.11 (WiFi) radio, a position location e.g., Global PositioningSystem (GPS)) radio, and a Bluetooth radio, where two of the above orall four may operate simultaneously. While the different radios provideuseful functionalities for the phone, their inclusion in a single devicegives rise to coexistence issues. Specifically, operation of one radiomay in some cases interfere with operation of another radio throughradiative, conductive, and/or resource collision, other interferencemechanisms. Coexistence issues include such interference.

This is especially true for the LTE uplink channel, which is adjacent tothe Industrial Scientific and Medical (ISM) band and may causeinterference therewith It is noted that Bluetooth and some Wireless LAN(WLAN) channels fall within the ISM band. In some instances, a Bluetootherror rate can become unacceptable when LTE is active in some channelsof Band 7 or even Band 40 for some Bluetooth channel conditions. Eventhough there is no significant degradation to LTE, simultaneousoperation with Bluetooth can result in disruption in voice servicesterminating in a Bluetooth headset. Such disruption may be unacceptableto the consumer. A similar issue exists when LTE transmissions interferewith position location. Currently, there is no mechanism that can solvethis issue because LTE by itself does not experience any degradation.

With reference specifically to LTE, it is noted that a UE communicateswith an evolved NodeB (eNB; e.g., a base station for a wirelesscommunications network) to inform the eNB of interference seen by the UEon the downlink. Furthermore, the eNB may be able to estimateinterference at the UE using a downlink error rate. In some instances,the eNB and the UE can cooperate to find a solution that reducesinterference at the UE, even interference due to radios within the UEitself. However, in conventional LTE, the interference estimatesregarding the downlink may not be adequate to comprehensively addressinterference.

In one instance, an LTE uplink signal interferes with a Bluetooth signalor WLAN signal. However, such interference is not reflected in thedownlink measurement reports at the eNB. As a result, unilateral actionon the part of the UE (e.g., moving the uplink signal to a differentchannel) may be thwarted by the eNB, which is not aware of the uplinkcoexistence issue and seeks to undo the unilateral action. For instance,even if the UE re-establishes the connection on a different frequencychannel, the network can still handover the UE back to the originalfrequency channel that was corrupted by the in-device interference. Thisis a likely scenario because the desired signal strength on thecorrupted channel may sometimes be higher than reflected in themeasurement reports of the new channel based on Reference SignalReceived Power (RSRP) to the eNB. Hence, a ping-pong effect of beingtransferred back and forth between the corrupted channel and the desiredchannel can happen if the eNB uses RSRP reports to inform handoverdecisions.

Other unilateral action on the part of the UE, such as simply stoppinguplink communications without coordination of the eNB may cause powerloop malfunctions at the eNB. Additional issues that exist inconventional LTE include a general lack of ability on the part of the UEto suggest desired configurations as an alternative to configurationsthat have coexistence issues. For at least these reasons, uplinkcoexistence issues at the UE may remain unresolved for a long timeperiod, degrading performance and efficiency of other radios of the UE.

SUMMARY

According to an aspect of the present disclosure, a method of wirelesscommunication includes identifying at least one coexistence issuecorresponding to a set of communication resources of a User Equipment(UE). The method also includes communicating an indication of thecoexistence issue(s) to a base station.

In another aspect, a method of wireless communication includes receivingsignaling, via a radio technology, from a served User Equipment (UE)relating to coexistence issues experienced by the served UE. The methodalso includes assigning at least one parameter associated withcommunication at the served UE, in response to the signaling, tomitigate the coexistence issues experienced by the served UE.

In another aspect, an apparatus is operable in a wireless communicationsystem. The apparatus has means for identifying at least one coexistenceissue corresponding to a set of communication resources of a UserEquipment (UE). The apparatus also has means for communicating anindication of the coexistence issue(s) to a base station.

In yet another aspect, an apparatus is operable in a wirelesscommunication system. The apparatus has means for receiving signalingfrom a served User Equipment (UE) relating to coexistence issuesexperienced by the served UE. The apparatus also has means for assigningat least one parameter associated with communication at the served UE,in response to the signaling, to mitigate the coexistence issuesexperienced by the served UE.

In still another aspect, an apparatus for wireless communication has amemory, and at least one processor coupled to the memory. Theprocessor(s) is configured to identify at least one coexistence issuecorresponding to a set of communication resources of a User Equipment(UE). The at least one processor is also configured to communicate anindication of the coexistence issue(s) to a base station.

In another aspect, an apparatus for wireless communication, has amemory, and at least one processor coupled to the memory. Theprocessor(s) is configured to receive signaling from a served UserEquipment (UE) relating to coexistence issues experienced by the servedUE. The processor is also configured to assign at least one parameterassociated with communication at the served UE, in response to thesignaling, to mitigate the coexistence issues experienced by the servedUE.

In a further aspect, a computer program product for wirelesscommunications in a wireless network has a computer-readable mediumhaving program code recorded thereon. The program code includes programcode to identify at least one coexistence issue corresponding to a setof communication resources of a User Equipment (UE). The program codealso includes program code to communicate an indication of thecoexistence issue(s) to a base station.

In another aspect, a computer program product for wirelesscommunications in a wireless network has a computer-readable mediumhaving program code recorded thereon. The program code includes programcode to receive signaling from a served User Equipment (UE) relating tocoexistence issues experienced by the served UE. The program code alsoincludes program code to assign at least one parameter associated withcommunication at the served UE, in response to the signaling, tomitigate the coexistence issues experienced by the served UE.

BRIEF DESCRIPTION OF THE DRAWINGS

The features, nature, and advantages of the present disclosure willbecome more apparent from the detailed description set forth below whentaken in conjunction with the drawings in which like referencecharacters identify correspondingly throughout.

FIG. 1 illustrates a multiple access wireless communication systemaccording to one aspect.

FIG. 2 is a block diagram of a communication system according to oneaspect.

FIG. 3 illustrates an exemplary frame structure in downlink Long TermEvolution (LTE) communications.

FIG. 4 is a block diagram conceptually illustrating an exemplary framestructure in uplink Long Term Evolution (LTE) communications.

FIG. 5 illustrates an example wireless communication environment.

FIG. 6 is a block diagram of an example design for a multi-radiowireless device.

FIG. 7 is graph showing respective potential collisions between sevenexample radios in a given decision period.

FIG. 8 is a diagram showing operation of an example Coexistence Manager(CxM) over time.

FIG. 9 is a block diagram of a system for providing support within awireless communication environment for multi-radio coexistencemanagement according to one aspect.

FIG. 10 illustrates a methodology that facilitates implementation ofmulti-radio coexistence functionality within a wireless communicationsystem.

FIG. 11 illustrates a methodology that facilitates implementation ofmulti-radio coexistence functionality within a wireless communicationsystem.

FIGS. 12A and B show exemplary timelines with respect to a short termgap.

DETAILED DESCRIPTION

Various aspects of the disclosure provide techniques to mitigatecoexistence issues in multi-radio devices. As explained above, somecoexistence issues persist because an eNB is not aware of interferenceon the UE side that is experienced by other radios. According to oneaspect, a UE identifies existing or potential coexistence issues andsends a message to the eNB that indicates that a coexistence issueexists. The message can include an identification of resourcesexperiencing coexistence issues, an identification of resources that areexperiencing fewer (or no) coexistence issues, an indication that someLTE events are being denied in arbitration at the UE, a modified ChannelQuality Indicator (CQI), a modified Power Headroom Report (PHR), or anyother helpful information. The eNB then knows that a coexistence issueexists at the UE and can select and implement mechanisms to aid the UEin mitigating the coexistence issues. Examples are described in moredetail below.

The techniques described herein can be used for various wirelesscommunication networks such as Code Division Multiple Access (CDMA)networks, Time Division Multiple Access (TDMA) networks, FrequencyDivision Multiple Access (FDMA) networks, Orthogonal FDMA (OFDMA)networks, Single-Carrier FDMA (SC-FDMA) networks, etc. The terms“networks” and “systems” are often used interchangeably. A CDMA networkcan implement a radio technology such as Universal Terrestrial RadioAccess (UTRA), cdma2000, etc. UTRA includes Wideband-CDMA (W-CDMA) andLow Chip Rate (LCR). cdma2000 covers IS-2000, IS-95 and IS-856standards. A TDMA network can implement a radio technology such asGlobal System for Mobile Communications (GSM). An OFDMA network canimplement a radio technology such as Evolved UTRA (E-UTRA), IEEE 802.11,IEEE 802.16, IEEE 802.20, Flash-OFDM®, etc. UTRA, E-UTRA, and GSM arepart of Universal Mobile Telecommunication System (UMTS). Long TermEvolution (LTE) is an upcoming release of UMTS that uses E-UTRA. UTRA,E-UTRA, GSM, UMTS, and LTE are described in documents from anorganization named “3^(rd) Generation Partnership Project” (3GPP).cdma2000 is described in documents from an organization named “3^(rd)Generation Partnership Project 2” (3GPP2). These various radiotechnologies and standards are known in the art. For clarity, certainaspects of the techniques are described below for LTE, and LTEterminology is used in portions of the description below.

Single carrier frequency division multiple access (SC-FDMA), whichutilizes single carrier modulation and frequency domain equalization isa technique that can be utilized with various aspects described herein.SC-FDMA has similar performance and essentially the same overallcomplexity as those of an OFDMA system. SC-FDMA signal has lowerpeak-to-average power ratio (PAPR) because of its inherent singlecarrier structure. SC-FDMA has drawn great attention, especially in theuplink communications where lower PAPR greatly benefits the mobileterminal in terms of transmit power efficiency. It is currently aworking assumption for an uplink multiple access scheme in 3GPP LongTerm Evolution (LTE), or Evolved UTRA.

Referring to FIG. 1, a multiple access wireless communication systemaccording to one aspect is illustrated. An evolved Node B 100 (eNB)includes a computer 115 that has processing resources and memoryresources to manage the LTE communications by allocating resources andparameters, granting/denying requests from user equipment, and/or thelike. The eNB 100 also has multiple antenna groups, one group includingantenna 104 and antenna 106, another group including antenna 108 andantenna 110, and an additional group including antenna 112 and antenna114. In FIG. 1, only two antennas are shown for each antenna group,however, more or fewer antennas can be utilized for each antenna group.A User Equipment (UE) 116 (also referred to as an Access Terminal (AT))is in communication with antennas 112 and 114, while antennas 112 and114 transmit information to the UE 116 over a downlink (DL) 120 andreceive information from the UE 116 over an uplink (UL) 118. The UE 122is in communication with antennas 106 and 108, while antennas 106 and108 transmit information to the UE 122 over a downlink (DL) 126 andreceive information from the UE 122 over an uplink 124. In an FDDsystem, communication links 118, 120, 124, and 126 can use differentfrequencies for communication. For example, the downlink 120 can use adifferent frequency than used by the uplink 118.

Each group of antennas and/or the area in which they are designed tocommunicate is often referred to as a sector of the eNB. In this aspect,respective antenna groups are designed to communicate to UEs in a sectorof the areas covered by the eNB 100.

In communication over the downlinks 120 and 126, the transmittingantennas of the eNB 100 utilize beamforming to improve thesignal-to-noise ratio of the uplinks for the different UEs 116 and 122.Also, an eNB using beamforming to transmit to UEs scattered randomlythrough its coverage causes less interference to UEs in neighboringcells than a UE transmitting through a single antenna to all its UEs.

An eNB can be a fixed station used for communicating with the terminalsand can also be referred to as an access point, base station, or someother terminology. A UE can also be called an access terminal, awireless communication device, terminal, or some other terminology.

FIG. 2 is a block diagram of an aspect of a transmitter system 210 (alsoknown as an eNB) and a receiver system 250 (also known as a UE) in aMIMO system 200. In some instances, both a UE and an eNB each have atransceiver that includes a transmitter system and a receiver system. Atthe transmitter system 210, traffic data for a number of data streams isprovided from a data source 212 to a transmit (TX) data processor 214.

A MIMO system employs multiple (NT) transmit antennas and multiple (NR)receive antennas for data transmission. A MIMO channel formed by the NTtransmit and NR receive antennas may be decomposed into Ns independentchannels, which are also referred to as spatial channels, whereinNs<min{NT, NR}. Each of the Ns independent channels corresponds to adimension. The MIMO system can provide improved performance (e.g.,higher throughput and/or greater reliability) if the additionaldimensionalities created by the multiple transmit and receive antennasare utilized.

A MIMO system supports time division duplex (TDD) and frequency divisionduplex (FDD) systems. In a TDD system, the uplink and downlinktransmissions are on the same frequency region so that the reciprocityprinciple allows the estimation of the downlink channel from the uplinkchannel. This enables the eNB to extract transmit beamforming gain onthe downlink when multiple antennas are available at the eNB.

In an aspect, each data stream is transmitted over a respective transmitantenna. The TX data processor 214 formats, codes, and interleaves thetraffic data for each data stream based on a particular coding schemeselected for that data stream to provide coded data.

The coded data for each data stream can be multiplexed with pilot datausing OFDM techniques. The pilot data is a known data pattern processedin a known manner and can be used at the receiver system to estimate thechannel response. The multiplexed pilot and coded data for each datastream is then modulated (e.g., symbol mapped) based on a particularmodulation scheme (e.g., BPSK, QSPK, M-PSK, or M-QAM) selected for thatdata stream to provide modulation symbols. The data rate, coding, andmodulation for each data stream can be determined by instructionsperformed by a processor 230 operating with a memory 232.

The modulation symbols for respective data streams are then provided toa TX MIMO processor 220, which can further process the modulationsymbols (e.g., for OFDM). The TX MIMO processor 220 then provides NTmodulation symbol streams to NT transmitters (TMTR) 222 a through 222 t.In certain aspects, the TX MIMO processor 220 applies beamformingweights to the symbols of the data streams and to the antenna from whichthe symbol is being transmitted.

Each transmitter 222 receives and processes a respective symbol streamto provide one or more analog signals, and further conditions (e.g.,amplifies, filters, and upconverts) the analog signals to provide amodulated signal suitable for transmission over the MIMO channel. NTmodulated signals from the transmitters 222 a through 222 t are thentransmitted from NT antennas 224 a through 224 t, respectively.

At a receiver system 250, the transmitted modulated signals are receivedby NR antennas 252 a through 252 r and the received signal from eachantenna 252 is provided to a respective receiver (RCVR) 254 a through254 r. Each receiver 254 conditions (e.g., filters, amplifies, anddownconverts) a respective received signal, digitizes the conditionedsignal to provide samples, and further processes the samples to providea corresponding “received” symbol stream.

An RX data processor 260 then receives and processes the NR receivedsymbol streams from NR receivers 254 based on a particular receiverprocessing technique to provide NR “detected” symbol streams. The RXdata processor 260 then demodulates, deinterleaves, and decodes eachdetected symbol stream to recover the traffic data for the data stream.The processing by the RX data processor 260 is complementary to theprocessing performed by the TX MIMO processor 220 and the TX dataprocessor 214 at the transmitter system 210.

A processor 270 (operating with a memory 272) periodically determineswhich pre-coding matrix to use (discussed below). The processor 270formulates an uplink message having a matrix index portion and a rankvalue portion.

The uplink message can include various types of information regardingthe communication link and/or the received data stream. The uplinkmessage is then processed by a TX data processor 238, which alsoreceives traffic data for a number of data streams from a data source236, modulated by a modulator 280, conditioned by transmitters 254 athrough 254 r, and transmitted back to the transmitter system 210.

At the transmitter system 210, the modulated signals from the receiversystem 250 are received by antennas 224, conditioned by receivers 222,demodulated by a demodulator 240, and processed by an RX data processor242 to extract the uplink message transmitted by the receiver system250. The processor 230 then determines which pre-coding matrix to usefor determining the beamforming weights, then processes the extractedmessage.

FIG. 3 is a block diagram conceptually illustrating an exemplary framestructure in downlink Long Term Evolution (LTE) communications. Thetransmission timeline for the downlink may be partitioned into units ofradio frames. Each radio frame may have a predetermined duration (e.g.,10 milliseconds (ms)) and may be partitioned into 10 subframes withindices of 0 through 9. Each subframe may include two slots. Each radioframe may thus include 20 slots with indices of 0 through 19. Each slotmay include L symbol periods, e.g., 7 symbol periods for a normal cyclicprefix (as shown in FIG. 3) or 6 symbol periods for an extended cyclicprefix. The 2L symbol periods in each subframe may be assigned indicesof 0 through 2L−1. The available time frequency resources may bepartitioned into resource blocks. Each resource block may cover Nsubcarriers (e.g., 12 subcarriers) in one slot.

In LTE, an eNB may send a Primary Synchronization Signal (PSS) and aSecondary Synchronization Signal (SSS) for each cell in the eNB. The PSSand SSS may be sent in symbol periods 6 and 5, respectively, in each ofsubframes 0 and 5 of each radio frame with the normal cyclic prefix, asshown in FIG. 3. The synchronization signals may be used by UEs for celldetection and acquisition. The eNB may send a Physical Broadcast Channel(PBCH) in symbol periods 0 to 3 in slot 1 of subframe 0. The PBCH maycarry certain system information.

The eNB may send a Cell-specific Reference Signal (CRS) for each cell inthe eNB. The CRS may be sent in symbols 0, 1, and 4 of each slot in caseof the normal cyclic prefix, and in symbols 0, 1, and 3 of each slot incase of the extended cyclic prefix. The CRS may be used by UEs forcoherent demodulation of physical channels, timing and frequencytracking, Radio Link Monitoring (RLM), Reference Signal Received Power(RSRP), and Reference Signal Received Quality (RSRQ) measurements, etc.

The eNB may send a Physical Control Format Indicator Channel (PCFICH) inthe first symbol period of each subframe, as seen in FIG. 3. The PCFICHmay convey the number of symbol periods (M) used for control channels,where M may be equal to 1, 2, or 3 and may change from subframe tosubframe. M may also be equal to 4 for a small system bandwidth, e.g.,with less than 10 resource blocks. In the example shown in FIG. 3, M=3.The eNB may send a Physical HARQ Indicator Channel (PHICH) and aPhysical Downlink Control Channel (PDCCH) in the first M symbol periodsof each subframe. The PDCCH and PHICH are also included in the firstthree symbol periods in the example shown in FIG. 3. The PHICH may carryinformation to support Hybrid Automatic Repeat Request (HARQ). The PDCCHmay carry information on resource allocation for UEs and controlinformation for downlink channels. The eNB may send a Physical DownlinkShared Channel (PDSCH) in the remaining symbol periods of each subframe.The PDSCH may carry data for UEs scheduled for data transmission on thedownlink. The various signals and channels in LTE are described in 3GPPTS 36.211, entitled “Evolved Universal Terrestrial Radio Access(E-UTRA); Physical Channels and Modulation,” which is publiclyavailable.

The eNB may send the PSS, SSS, and PBCH in the center 1.08 MHz of thesystem bandwidth used by the eNB. The eNB may send the PCFICH and PHICHacross the entire system bandwidth in each symbol period in which thesechannels are sent. The eNB may send the PDCCH to groups of UEs incertain portions of the system bandwidth. The eNB may send the PDSCH tospecific UEs in specific portions of the system bandwidth. The eNB maysend the PSS, SSS, PBCH, PCFICH, and PHICH in a broadcast manner to allUEs, may send the PDCCH in a unicast manner to specific UEs, and mayalso send the PDSCH in a unicast manner to specific UEs.

A number of resource elements may be available in each symbol period.Each resource element may cover one subcarrier in one symbol period andmay be used to send one modulation symbol, which may be a real orcomplex value. Resource elements not used for a reference signal in eachsymbol period may be arranged into resource element groups (REGs). EachREG may include four resource elements in one symbol period. The PCFICHmay occupy four REGs, which may be spaced approximately equally acrossfrequency, in symbol period 0. The PHICH may occupy three REGs, whichmay be spread across frequency, in one or more configurable symbolperiods. For example, the three REGs for the PHICH may all belong insymbol period 0 or may be spread in symbol periods 0, 1, and 2. ThePDCCH may occupy 9, 18, 32 or 64 REGs, which may be selected from theavailable REGs, in the first M symbol periods. Only certain combinationsof REGs may be allowed for the PDCCH.

A UE may know the specific REGs used for the PHICH and the PCFICH. TheUE may search different combinations of REGs for the PDCCH. The numberof combinations to search is typically less than the number of allowedcombinations for the PDCCH. An eNB may send the PDCCH to the UE in anyof the combinations that the UE will search.

FIG. 4 is a block diagram conceptually illustrating an exemplary framestructure 300 in uplink Long Term Evolution (LTE) communications. Theavailable Resource Blocks (RBs) for the uplink may be partitioned into adata section and a control section. The control section may be formed atthe two edges of the system bandwidth and may have a configurable size.The resource blocks in the control section may be assigned to UEs fortransmission of control information. The data section may include allresource blocks not included in the control section. The design in FIG.4 results in the data section including contiguous subcarriers, whichmay allow a single UE to be assigned all of the contiguous subcarriersin the data section.

A UE may be assigned resource blocks in the control section to transmitcontrol information to an eNB. The UE may also be assigned resourceblocks in the data section to transmit data to the eNodeB. The UE maytransmit control information in a Physical Uplink Control Channel(PUCCH) on the assigned resource blocks in the control section. The UEmay transmit only data or both data and control information in aPhysical Uplink Shared Channel (PUSCH) on the assigned resource blocksin the data section. An uplink transmission may span both slots of asubframe and may hop across frequency as shown in FIG. 4.

The PSS, SSS, CRS, PBCH, PUCCH and PUSCH in LTE are described in 3GPP TS36.211, entitled “Evolved Universal Terrestrial Radio Access (E-UTRA);Physical Channels and Modulation,” which is publicly available.

In an aspect, described herein are systems and methods for providingsupport within a wireless communication environment, such as a 3GPP LTEenvironment or the like, to facilitate multi-radio coexistencesolutions.

Referring now to FIG. 5, illustrated is an example wirelesscommunication environment 500 in which various aspects described hereincan function. The wireless communication environment 500 can include awireless device 510, which can be capable of communicating with multiplecommunication systems. These systems can include, for example, one ormore cellular systems 520 and/or 530, one or more WLAN systems 540and/or 550, one or more wireless personal area network (WPAN) systems560, one or more broadcast systems 570, one or more satellitepositioning systems 580, other systems not shown in FIG. 5, or anycombination thereof. It should be appreciated that in the followingdescription the terms “network” and “system” are often usedinterchangeably.

The cellular systems 520 and 530 can each be a CDMA, TDMA, FDMA, OFDMA,Single Carrier FDMA (SC-FDMA), or other suitable system. A CDMA systemcan implement a radio technology such as Universal Terrestrial RadioAccess (UTRA), cdma2000, etc. UTRA includes Wideband CDMA (WCDMA) andother variants of CDMA. Moreover, cdma2000 covers IS-2000 (CDMA2000 1×),IS-95 and IS-856 (HRPD) standards. A TDMA system can implement a radiotechnology such as Global System for Mobile Communications (GSM),Digital Advanced Mobile Phone System (D-AMPS), etc. An OFDMA system canimplement a radio technology such as Evolved UTRA (E-UTRA), Ultra MobileBroadband (UMB), IEEE 802.16 (WiMAX), IEEE 802.20, Flash-OFDM®, etc.UTRA and E-UTRA are part of Universal Mobile Telecommunication System(UMTS). 3GPP Long Term Evolution (LTE) and LTE-Advanced (LTE-A) are newreleases of UMTS that use E-UTRA. UTRA, E-UTRA, UMTS, LTE, LTE-A and GSMare described in documents from an organization named “3^(rd) GenerationPartnership Project” (3GPP). cdma2000 and UMB are described in documentsfrom an organization named “3^(rd) Generation Partnership Project 2”(3GPP2). In an aspect, the cellular system 520 can include a number ofbase stations 522, which can support bi-directional communication forwireless devices within their coverage. Similarly, the cellular system530 can include a number of base stations 532 that can supportbi-directional communication for wireless devices within their coverage.

WLAN systems 540 and 550 can respectively implement radio technologiessuch as IEEE 802.11 (Wi-Fi), Hiperlan, etc. The WLAN system 540 caninclude one or more access points 542 that can support bi-directionalcommunication. Similarly, the WLAN system 550 can include one or moreaccess points 552 that can support bi-directional communication. TheWPAN system 560 can implement a radio technology such as Bluetooth (BT),IEEE 802.15, etc. Further, the WPAN system 560 can supportbi-directional communication for various devices such as wireless device510, a headset 562, a computer 564, a mouse 566, or the like.

The broadcast system 570 can be a television (TV) broadcast system, afrequency modulation (FM) broadcast system, a digital broadcast system,etc. A digital broadcast system can implement a radio technology such asMediaFLO™, Digital Video Broadcasting for Handhelds (DVB-H), IntegratedServices Digital Broadcasting for Terrestrial Television Broadcasting(ISDB-T), or the like. Further, the broadcast system 570 can include oneor more broadcast stations 572 that can support one-way communication.

The satellite positioning system 580 can be the United States GlobalPositioning System (GPS), the European Galileo system, the RussianGLONASS system, the Quasi-Zenith Satellite System (QZSS) over Japan, theIndian Regional Navigational Satellite System (IRNSS) over India, theBeidou system over China, and/or any other suitable system. Further, thesatellite positioning system 580 can include a number of satellites 582that transmit signals for position determination.

In an aspect, the wireless device 510 can be stationary or mobile andcan also be referred to as a user equipment (UE), a mobile station, amobile equipment, a terminal, an access terminal, a subscriber unit, astation, etc. The wireless device 510 can be cellular phone, a personaldigital assistance (PDA), a wireless modem, a handheld device, a laptopcomputer, a cordless phone, a wireless local loop (WLL) station, etc. Inaddition, a wireless device 510 can engage in two-way communication withthe cellular system 520 and/or 530, the WLAN system 540 and/or 550,devices with the WPAN system 560, and/or any other suitable systems(s)and/or devices(s). The wireless device 510 can additionally oralternatively receive signals from the broadcast system 570 and/orsatellite positioning system 580. In general, it can be appreciated thatthe wireless device 510 can communicate with any number of systems atany given moment. Also, the wireless device 510 may experiencecoexistence issues among various ones of its constituent radio devicesthat operate at the same time. Accordingly, device 510 includes acoexistence manager (CxM, not shown) that has a functional module todetect and mitigate coexistence issues, as well as to report oncoexistence issues, as explained further below.

Turning next to FIG. 6, a block diagram is provided that illustrates anexample design for a multi-radio wireless device 600 and may be used asan implementation of the wireless device 510 of FIG. 5. As FIG. 6illustrates, the wireless device 600 can include N radios 620 a through620 n, which can be coupled to N antennas 610 a through 610 n,respectively, where N can be any integer value. It should beappreciated, however, that respective radios 620 can be coupled to anynumber of antennas 610 and that multiple radios 620 can also share agiven antenna 610.

In general, a radio 620 can be a unit that radiates or emits energy inan electromagnetic spectrum, receives energy in an electromagneticspectrum, or generates energy that propagates via conductive means. Byway of example, a radio 620 can be a unit that transmits a signal to asystem or a device or a unit that receives signals from a system ordevice. Accordingly, it can be appreciated that a radio 620 can beutilized to support wireless communication. In another example, a radio620 can also be a unit (e.g., a screen on a computer, a circuit board,etc.) that emits noise, which can impact the performance of otherradios. Accordingly, it can be further appreciated that a radio 620 canalso be a unit that emits noise and interference without supportingwireless communication.

In an aspect, respective radios 620 can support communication with oneor more systems. Multiple radios 620 can additionally or alternativelybe used for a given system, e.g., to transmit or receive on differentfrequency bands (e.g., cellular and PCS bands).

In another aspect, a digital processor 630 can be coupled to radios 620a through 620 n and can perform various functions, such as processingfor data being transmitted or received via the radios 620. Theprocessing for each radio 620 can be dependent on the radio technologysupported by that radio and can include encryption, encoding,modulation, etc., for a transmitter; demodulation, decoding, decryption,etc., for a receiver, or the like. In one example, the digital processor630 can include a CxM 640 that can control operation of the radios 620in order to improve the performance of the wireless device 600 asgenerally described herein. The CxM 640 can have access to a database644, which can store information used to control the operation of theradios 620.

Another function of the CxM 640 is arbitration among the constituentradios 620 so that operation of one of the radios may be deniedmomentarily for the benefit of another radio. Under some proposedcoexistence manager (CxM) architectures, some LTE uplink events may bedenied in arbitration in favor of allowing an ISM radio to transmit orreceive. However, denying uplink events leads to other issues, asdiscussed further below. Accordingly, it would be desirable to implementmechanisms to reduce the instances where LTE is denied; additionally, itwould be desirable to mitigate the impact to the overall LTE system whenevents are denied.

As explained further below, the CxM 640 can be adapted for a variety oftechniques to decrease interference between the radios. In one example,the CxM 640 reports coexistence issues to the serving eNB. In anotherexample, the CxM 640 sends a modified CQI or a PHR to the eNB thatcauses the eNB to alter communication parameters with the UE in order todecrease the impact of coexistence issues.

For simplicity, digital processor 630 is shown in FIG. 6 as a singleprocessor. However, it should be appreciated that the digital processor630 can include any number of processors, controllers, memories, etc. Inone example, a controller/processor 650 can direct the operation ofvarious units within the wireless device 600. Additionally oralternatively, a memory 652 can store program codes and data for thewireless device 600. The digital processor 630, controller/processor650, and memory 652 can be implemented on one or more integratedcircuits (ICs), application specific integrated circuits (ASICs), etc.By way of specific, non-limiting example, the digital processor 630 canbe implemented on a Mobile Station Modem (MSM) ASIC.

In an aspect, the CxM 640 can manage operation of respective radios 620utilized by wireless device 600 in order to avoid interference and/orother performance degradation associated with collisions betweenrespective radios 620. CxM 640 may perform one or more processes, suchas that illustrated in FIG. 10. By way of further illustration, a graph700 in FIG. 7 represents respective potential collisions between sevenexample radios in a given decision period. In the example shown in graph700, the seven radios include a WLAN transmitter (Tw), an LTEtransmitter (Tl), an FM transmitter (Tf), a GSM/WCDMA transmitter(Tc/Tw), an LTE receiver (Rl), a Bluetooth receiver (Rb), and a GPSreceiver (Rg). The four transmitters are represented by four nodes onthe left side of the graph 700. The four receivers are represented bythree nodes on the right side of the graph 700.

A potential collision between a transmitter and a receiver isrepresented on the graph 700 by a branch connecting the node for thetransmitter and the node for the receiver. Accordingly, in the exampleshown in the graph 700, collisions may exist between (1) the WLANtransmitter (Tw) and the Bluetooth receiver (Rb); (2) the LTEtransmitter (Tl) and the Bluetooth receiver (Rb); (3) the WLANtransmitter (Tw) and the LTE receiver (Rl); (4) the FM transmitter (Tf)and the GPS receiver (Rg); (5) a WLAN transmitter (Tw), a GSM/WCDMAtransmitter (Tc/Tw), and a GPS receiver (Rg).

In one aspect, an example CxM 640 can operate in time in a manner suchas that shown by diagram 800 in FIG. 8. As diagram 800 illustrates, atimeline for CxM operation can be divided into Decision Units (DUs),which can be any suitable uniform or non-uniform length (e.g., 100 μs)where notifications are processed, and a response phase (e.g., 20 μs)where commands are provided to various radios 620 and/or otheroperations are performed based on actions taken in the evaluation phase.In one example, the timeline shown in the diagram 800 can have a latencyparameter defined by a worst case operation of the timeline, e.g., thetiming of a response in the case that a notification is obtained from agiven radio immediately following termination of the notification phasein a given DU.

In-device coexistence problems can exist with respect to a UE betweenresources such as, for example, LTE and ISM bands (e.g., forBluetooth/WLAN). In current LTE implementations, any interference issuesto LTE are reflected in the DL measurements (e.g., Reference SignalReceived Quality (RSRQ) metrics, etc.) reported by the UE and/or the DLerror rate which the eNB can use to make inter-frequency or inter-RAThandoff decisions to, e.g., move LTE to a channel or RAT with nocoexistence issues. However, it can be appreciated that these existingtechniques will not work if, for example, the LTE UL is causinginterference to Bluetooth/WLAN but the LTE DL does not see anyinterference from Bluetooth/WLAN. More particularly, even if the UEautonomously moves itself to another channel on the UL, the eNB can insome cases handover the UE back to the problematic channel for loadbalancing purposes. In any case, it can be appreciated that existingtechniques do not facilitate use of the bandwidth of the problematicchannel in the most efficient way.

Also, in-device coexistence problems can exist with respect to a UEbetween resources such as, for example, LTE and ISM bands (e.g., forBluetooth/WLAN). Further, under some proposed CxM architectures, it canbe appreciated that some events, such as LTE UL events, may be denied inarbitration. Accordingly, it would be desirable to implement mechanismsto reduce the instances where radios, such as LTE radios are denied.Additionally, it would be desirable to mitigate the impact to theoverall system (e.g., the overall LTE system) when events are denied.

Turning now to FIG. 9, a block diagram of a system 900 for providingsupport within a wireless communication environment for multi-radiocoexistence management is illustrated. In an aspect, the system 900 caninclude one or more UEs 910 and/or eNBs 930, which can engage in UL, DL,and/or any other suitable communication with each other and/or any otherentities in the system 900. In one example, the UE 910 and/or eNB 930can be operable to communicate using a variety of resources, includingfrequency channels, and sub-bands, some of which can potentially becolliding with other radio resources (e.g., a Bluetooth radio). The UE910 and eNB 930 can utilize various techniques for managing coexistencebetween multiple radios of the UE 910, as generally described herein.

To mitigate at least the above shortcomings, the UE 910 and the eNB 930can utilize respective features described herein and illustrated by thesystem 900 to facilitate support for multi-radio coexistence within theUE 910. The various modules 912-918 may be, in some examples,implemented as part of a coexistence manager such as the CxM 640 of FIG.6.

In an aspect, the UE 910 can utilize a notification module 918, incooperation with other mechanisms such as a radio capability analyzer912 and/or the resource coexistence analyzer 914, to indicate to the eNB930 in a message that the UE 910 is experiencing a coexistence problemwith, e.g., Bluetooth or WLAN.

The resource coexistence analyzer 914 recognizes that unacceptableperformance occurs or is expected to occur due to interference. In oneexample, the resource coexistence analyzer 914 is equipped to detectinterference. Additionally or alternatively, the resource coexistenceanalyzer 914 may be programmed to know that when certain radios usecertain channels, coexistence issues are necessarily present.Additionally or alternatively, the resource coexistence analyzer 914 maybe programmed to know that certain radios operating at the same timewill necessarily have coexistence issues.

The message sent from the UE 910 to the eNB 930 can be, for example, astatic one-time capability indication of multi-radio use withBluetooth/WLAN (i.e., a static indication of multi-radio capability), adynamic message that indicates when Bluetooth/WLAN is turned ON or whenit is turned OFF, or the like. In one example, the eNB 930 can utilize anotification analyzer 922, a scheduling module 924, and/or othersuitable means to select and implement techniques to aid the UE 910 inmitigating the coexistence solution. These techniques can include, forexample, a handover to another frequency or RAT, use of a measurementgap pattern or DRX cycle that prevents operation of the LTE radio duringperiods where other radios can operate, etc.

In one example scenario, the UE 910 sends a message to the eNB 930alerting the eNB 930 to coexistence issues at the UE 910. The eNB 930then initiates an inter-frequency or inter-RAT handover of the LTEcommunications. For instance, the eNB 930 may initiate a handover fromone LTE channel to another LTE channel or from LTE to another RAT, suchas GSM.

In a second example scenario, the UE 910 sends a message to the eNB 930alerting the eNB 930 to coexistence issues at the UE 910. The eNB 930then schedules a measurement gap pattern for the UE 910 that attempts tomitigate the interference issues by creating measurement gaps in theradio technology. The radio technology can be LTE or any othertechnology capable of providing gaps. Conventional LTE provides formeasurement gaps. The gaps can be created in either an interfering radiotechnology or a victim radio technology. An eNB 930 may instruct a UE910 to be silent (i.e., no uplink or downlink communications) every somany milliseconds of a cycle. Gaps currently provided include: 6 ms outof every 40 ms, and 6 ms out of every 80 ms. During the measurement gap,the UE 910 measures interfering signals in various channels. The UE 910then reports the information to the eNB 930, and the eNB 930 uses thereported information, e.g., to handover the LTE communications of the UE910 to another channel that should be expected to experience lessinterference. Measurement gap configuration is initiated by the eNB 930in conventional LTE systems.

In some aspects, new gap patterns are defined for the measurement gaps,where such new gap patterns provide evenly-distributed gaps that can beutilized by another radio. One example pattern includes 20 ms out of 40ms, and another example includes 30 ms out of 60 ms. In such example gappatterns, half of each cycle is a measurement gap and can be used byother radios. For instance, according to one example, 20 ms of every 40ms period can be used by a Bluetooth radio (and/or other radios) withoutLTE interference.

In one embodiment, the UE can influence the type and phase of the gappattern using the coexistence message. In one example, the eNB can use ameasurement gap of 20 ms over 40 ms with the start offset of the gapindicated by the UE in the coexistence message.

In a third example scenario, the UE 910 sends a message to the eNB 930alerting the eNB 930 to coexistence issues at the UE 910. The eNB 930then configures a discontinuous reception (DRX) mode cycle for the UE910 that attempts to mitigate the interference issues. The DRX cycleincludes the periodic switching off of an LTE receiver on the downlink,usually for power saving purposes. In conventional LTE, an eNB 930configures a DRX cycle for a UE 910. During the DRX cycle, the eNB 930knows times when the UE 910 is on and listens for downlink communicationand when the UE 910 is off and does not listen for downlinkcommunications. Uplink communications may proceed, even if the downlinkcommunications are in an off period. A DRX cycle includes 1) anonDuration, where the UE 910 is awake and listens for downlinkcommunications, 2) a period after the onDuration to accommodateactivities, such as receiving grants and resolving HARQ andretransmission, and 3) an inactive period.

The gap patterns can also be on a shorter time-scale to allow latencyconstrained voice traffic on a Bluetooth (or other) radio. For example,FIG. 12A shows a time-line 1200 for time division-long term evolution(TD-LTE) (Configuration 1) and a timeline of Bluetooth extendedsynchronous connections (eSCO) 1210 as a slave. The downlink time slots(i.e., receiving at the UE) are shown as solid, whereas the uplinktimeslots (i.e., transmitting from the UE are shown as shaded.) Withoutany gaps, Bluetooth packets are lost in three out of four eSCOintervals, where each eSCO interval is 3.75 ms. In FIGS. 12A and B, theslots having “Xs” represent slots with lost packets, whereas the slotshaving “checkmarks” represent slots having successful transmissions. Theslots without an X or checkmark in the Bluetooth timelines 1210, 1260represent slots where no transmission occurs.

Referring now to FIG. 12B, an embodiment of the present disclosure isdescribed in which a short term gap is created. For example, onedownlink and one uplink sub-frame can be removed in the middle of eachLTE frame (as seen in the timeline 1250). By creating a gap of, forexample, 2 ms every 5 ms in LTE, the previously lost Bluetooth packetscan be recovered, as shown in the Bluetooth timeline 1260 of FIG. 12B.More specifically, many of the slots having an “X” in the timeline 1210are indicated as including successfully transmitted packets in thetimeline 1260. The gap configuration in this example is merely exemplaryand other short-term gap configurations are also contemplated.

Various aspects may configure DRX cycles differently than inconventional LTE. For instance, the shortDRXcycle parameter is set tozero so that only a long DRX cycle is used. The active time after theonDuration can be restricted to 4 ms or some other small number ofmilliseconds to shorten the active time after the onDuration. Thedrx-InactivityTimer and drx-RestransmissionTimer parameters, whichconfigure the active time after onDuration, are set to zero (or anothersmall number such as one) to remove the additional active time to waitfor downlink grants. However, such specific values are exemplary, andother aspects may use different values.

In one implementation, the onDuration and 4 ms period following can beused by an LTE radio, while the time until the next onDuration can beused by another radio, such as a Bluetooth or WLAN radio. For instance,in one example based on these settings, LTE and Bluetooth/WLAN canutilize Time Division Multiplexing (TDM) with 34 ms for LTE and 30 msfor Bluetooth/WLAN, out of a 64 ms DRX cycle. Thus, the DRX cycle isshared in approximate halves between LTE and ISM, where the 4 ms periodafter onDuration is in the range of 1/16 of the DRX cycle length.

In an aspect, if the eNB 930 sends a NACK for any of the last fouruplink subframes of onDuration, the HARQ packet can be considered asterminated in error by both the eNB 930 and the UE 910. In other words,if there is an unsuccessful uplink transmission in the last foursubframes of the onDuration, then a NACK is sent to the UE 910 foursubframes later in the active time. In conventional LTE, the UE 910 willretransmit 4 ms after receiving the NACK; however, in some presentaspects, it is desirable for the UE 910 not to transmit after the activeperiod ends. Accordingly, the eNB 930 and the UE 910 can negotiate atimeline such that if a NACK is sent to the UE 910, the UE 910 will notretransmit. The packet is then terminated in error by both the UE 910and the eNB 930. Thus, the UE 910 does not transmit after the end of theactive period, and the eNB 930 can be made aware that the UE 910 willnot retransmit and can accordingly reassign those resources. In someinstances, the eNB 930 and the UE 910 may agree on a timeline in whichthe retransmission is sent in the next onDuration.

Thus, the eNB 930 may perform a handover, may configure a measurementgap pattern, and/or may configure a DRX cycle to mitigate thecoexistence issues. However, the scope of aspects is not limited tothose options, as other options for mitigating coexistence issues nowknown or later developed may be employed in other implementations.

In another aspect, the UE 910 can utilize a notification module 918, incooperation with other mechanisms such as a resource coexistenceanalyzer 914 or the like, to indicate to the eNB 930 one or moreportions of bandwidth where there is no coexistence issue. This can, forexample, enable the eNB 930 to schedule the LTE radio (e.g., via thescheduling module 924) in parts of the band with fewer (or no)coexistence issues while increasing or maximizing the availableresources for the UE 910.

In one embodiment, the indication is implicit. For example, a channelquality indicator (CQI) of a sub-band may be modified, leading the eNBto believe the channel quality is different (e.g., worse) that what itactually is. In another embodiment, the power of a transmitted signal,such as a sounding reference signal (SRS) could be modified. Forexample, if the UE reduces the transmit power of the SRS in a particularsub-band, then the eNB perceives the sub-band as a bad sub-band. Thesub-band CQI report modification and SRS power modification are implicittechniques for sub-band restriction on downlink and uplink,respectively. An explicit technique would be for the UE to indicate thecoexistence information of some sub-bands in a message.

In a further aspect, if the UE 910 has to continue a connection in aproblematic portion of the band, the UE 910 can, via the notificationmodule 918 and/or other suitable components, take steps to suggest tothe eNB 930 to avoid allocations that would lead to higher uplinktransmit power or a higher downlink SINR requirement. For instance, inuplink communications, scheduling is based on Power Headroom Reports(PHRs). The eNB 930 receives the PHR and assigns a certain rate to theuplink, which leads to a certain transmit power at the UE 910 based onthe content in the PHR. However, higher power (and higher rate) on theuplink can cause more interference with the other radios in the UE 910.In some aspects, the UE 910 chooses a lower PHR than what is reallyseen, and the PHR causes the eNB to assign a lower rate to the uplink.

Similarly, the downlink is scheduled by Channel Quality Indicator (CQI)reports sent from the UE 910 to the eNB 930. In some aspects, the UE 910sends a CQI report to the eNB 930 that causes the eNB 930 to assign alower rate to the UE 910 downlink. A lower rate at the downlink may leadto higher interference tolerance with other radios at the UE 910. In oneexample, lower uplink and downlink power requirements can reduce thechance that, e.g., Bluetooth/WLAN and LTE will not be able to coexist atthe UE 910.

In another aspect, the coexistence manager in the UE 910 forces LTEuplink communications to stop or the LTE downlink to stop receiving toallow an ISM event to go through. However, this may affect power controlbased on HARQ termination in conventional LTE systems at the eNB 930.

In conventional LTE, HARQ control and power loops run on an eNB 930 thatkeeps track of termination statistics and targets certain terminationstatistics. For example, some control loops may target an error rate,such as 70% proper termination at first transmission. If an LTE uplinkis simply shut off, then the control loops at the eNB 930 may miss thestatistics because it appears as additional errors to the control loops.This may cause improper loop behavior where thresholds are set lower andlower as the errors add up, a cycle that feeds on itself and causesinefficient operation. Similar effects may be seen in the downlink ratecontrol loops, due to the additional errors from a coexistencealgorithm.

Thus, in an aspect, the UE 910 can utilize the notification module 918in cooperation with mechanisms such as a CxM decision analyzer 916 toprovide a message to the eNB 930 indicating that, e.g., some LTE eventsare being denied. The eNB 930 then knows of the LTE event denial and canprevent the control loops from taking drastic steps in settingthresholds. In one embodiment, the denial of a radio event (e.g., an LTEevent) includes denial of a subframe, a frame, a block, aretransmission, an ACK, etc. Different metrics for the denials may bereported by the UE in the message to the eNB. For instance, the UE mayindicate to the eNB the average of the number of uplink and downlinksubframes denied due to coexistence every T milliseconds such as T=100.Another example is where the UE simply reports the probability of aparticular subframe being denied due to coexistence. Other examples arealso contemplated, such as when the UE reports the probability of aPUCCH transmission being denied.

In one embodiment, the message includes additional factors to apply to atarget termination threshold comparison when a coexistence solution istaking place at the UE 910. Such factors may include an indication ofthe existence of an error, an indication of expected frequency or numberof denials, and/or the like. Furthermore, the message can also includean explicit indication of the subframes denied by the CxM 640 due tocoexistence or some other metric that indicates how many uplinktransmissions are being denied. In other embodiments, the messageindicates a rate of subframe denial, a rate of frame denial, a rate ofblock denial, etc. Different denial rates could be reported. Forexample, an average for a time period, a time period average, aninstantaneous time, etc. could be reported. The rate of subframe denialcould be for a particular transmission. As mentioned earlier, the eNBmay target an error rate at a certain HARQ transmission number. If theUE reports the rate of denial of subframes for a particular HARQtransmission number, then the eNB can prevent unnecessary adjustment ofthe rate control loops because the eNB becomes aware of the extent oferrors due to coexistence itself in addition to the link errors. In oneembodiment, the UE provides enhanced measurement reports for thecondition of each frequency or RAT being reported. The enhancedmeasurement reports can include, for example, an interfering technologyidentifier and/or interfering direction information and/or the trafficpattern (e.g., mode of operation under Bluetooth).

The interfering technology indicator can identify the interferingtechnology on the device corresponding to the reported channel/RAT, suchas Bluetooth, WLAN, GPS, etc. The interfering technology indicator canalso specify the parameters associated with the traffic pattern on theinterfering technology, such as voice, data, Bluetooth eSCO, etc. TheeNB may use such information to configure measurement gaps on theuplink, downlink, or both.

The interfering direction information can include one bit to identifywhether the uplink of the reported channel/RAT is causing an in-devicecoexistence problem. Another bit can identify whether the downlink ofthe reported channel/RAT is experiencing degradation due to in-devicecoexistence. It may be possible that both bits are set to indicatecoexistence issues on both LTE uplink and downlink. The directioninformation identifies whether LTE is the aggressor, the victim or bothwith respect to the in-device interference. The interfering directioninformation can be used along with the interfering technology identifierin the measurement gap configuration at the eNB so the eNB can choosethe appropriate gap pattern to support coexistence.

FIG. 10 illustrates a methodology 1000 that facilitates implementationof multi-radio coexistence functionality within a wireless communicationsystem. The methodology 1000 may be performed, e.g., by a UEcommunicating with a base station, such as an eNB. At block 1002, one ormore coexistence issues corresponding to a utilized set of communicationresources (e.g., radio technologies or radio resources) are identified.The identification recognizes that unacceptable performance occurs or isexpected to occur due to interference. In one example, a device withmultiple radios is equipped to detect interference. Additionally oralternatively, the device may be programmed to know that when certainradios use certain channels, coexistence issues are necessarily present.Coexistence issues may be identified, e.g., by the CxM 640 of FIG. 6. Atblock 1004, an indication of the one or more coexistence issues iscommunicated to a serving base station.

FIG. 11 illustrates a methodology 1100 that facilitates implementationof multi-radio coexistence functionality within a wireless communicationsystem. The methodology 1100 may be performed, e.g., by an eNB or otherbase station communicating with a UE. At block 1102, signaling relatingto radio coexistence issues experienced by a served UE is received fromthe served UE via a first radio technology. At block 1104, one or moreparameters associated with communication at the served UE are assignedsuch that the radio coexistence issues experienced by the served UE arecompletely or substantially mitigated. In one example, the base stationperforms a handover. In another example, the base station configures ameasurement gap pattern or a DRX cycle to provide a TDM solution withLTE and the other resource. The base station may have multiple optionsto choose from and may select one or more of the options based on anycriteria.

The examples above describe aspects implemented in an LTE system.However, the scope of the disclosure is not so limited. Various aspectsmay be adapted for use with other communication systems, such as thosethat employ any of a variety of communication protocols including, butnot limited to, CDMA systems, TDMA systems, FDMA systems, and OFDMAsystems.

It is understood that the specific order or hierarchy of steps in theprocesses disclosed is an example of exemplary approaches. Based upondesign preferences, it is understood that the specific order orhierarchy of steps in the processes may be rearranged while remainingwithin the scope of the present disclosure. The accompanying methodclaims present elements of the various steps in a sample order, and arenot meant to be limited to the specific order or hierarchy presented.

Those of skill in the art would understand that information and signalsmay be represented using any of a variety of different technologies andtechniques. For example, data, instructions, commands, information,signals, bits, symbols, and chips that may be referenced throughout theabove description may be represented by voltages, currents,electromagnetic waves, magnetic fields or particles, optical fields orparticles, or any combination thereof.

Those of skill would further appreciate that the various illustrativelogical blocks, modules, circuits, and algorithm steps described inconnection with the aspects disclosed herein may be implemented aselectronic hardware, computer software, or combinations of both. Toclearly illustrate this interchangeability of hardware and software,various illustrative components, blocks, modules, circuits, and stepshave been described above generally in terms of their functionality.Whether such functionality is implemented as hardware or softwaredepends upon the particular application and design constraints imposedon the overall system. Skilled artisans may implement the describedfunctionality in varying ways for each particular application, but suchimplementation decisions should not be interpreted as causing adeparture from the scope of the present disclosure.

The various illustrative logical blocks, modules, and circuits describedin connection with the aspects disclosed herein may be implemented orperformed with a general purpose processor, a digital signal processor(DSP), an application specific integrated circuit (ASIC), a fieldprogrammable gate array (FPGA) or other programmable logic device,discrete gate or transistor logic, discrete hardware components, or anycombination thereof designed to perform the functions described herein.A general purpose processor may be a microprocessor, but in thealternative, the processor may be any conventional processor,controller, microcontroller, or state machine. A processor may also beimplemented as a combination of computing devices, e.g., a combinationof a DSP and a microprocessor, a plurality of microprocessors, one ormore microprocessors in conjunction with a DSP core, or any other suchconfiguration.

The steps of a method or algorithm described in connection with theaspects disclosed herein may be embodied directly in hardware, in asoftware module executed by a processor, or in a combination of the two.A software module may reside in RAM memory, flash memory, ROM memory,EPROM memory, EEPROM memory, registers, hard disk, a removable disk, aCD-ROM, or any other form of storage medium known in the art. Anexemplary storage medium is coupled to the processor such the processorcan read information from, and write information to, the storage medium.In the alternative, the storage medium may be integral to the processor.The processor and the storage medium may reside in an ASIC. The ASIC mayreside in a user terminal. In the alternative, the processor and thestorage medium may reside as discrete components in a user terminal.

The previous description of the disclosed aspects is provided to enableany person skilled in the art to make or use the present disclosure.Various modifications to these aspects will be readily apparent to thoseskilled in the art, and the generic principles defined herein may beapplied to other aspects without departing from the spirit or scope ofthe disclosure. Thus, the present disclosure is not intended to belimited to the aspects shown herein but is to be accorded the widestscope consistent with the principles and novel features disclosedherein.

What is claimed is:
 1. A method of wireless communication by a userequipment (UE), comprising: identifying a coexistence issuecorresponding to a set of communication resources of the UE;transmitting, to a base station, an indication of the coexistence issue;receiving, from the base station, a communication parameter forselectively scheduling a measurement gap pattern; and communicating inaccordance with the measurement gap pattern to mitigate the coexistenceissue.
 2. The method of claim 1, in which transmitting the indicationcomprises transmitting a static indication of a multi-radio capabilityof the UE, the static indication comprising a one-time indication ofexistence of radio resources in the UE.
 3. The method of claim 1, inwhich transmitting the indication comprises transmitting a messageindicating at least one of an enabled communication resource and adisabled communication resource.
 4. The method of claim 1, in whichtransmitting the indication comprises transmitting an indication of aportion of a bandwidth without coexistence issues.
 5. The method ofclaim 1, in which the indication corresponds to at least one of anuplink transmit power target or a downlink signal to interference ratiotarget.
 6. The method of claim 1, in which transmitting the indicationcomprises transmitting an indicator of an uplink transmission or adownlink transmission denied by the UE due to the coexistence issue. 7.The method of claim 1, in which transmitting the indication comprisestransmitting an indicator of a rate of subframe denial at the UE due tothe coexistence issue.
 8. The method of claim 7, in which the rate ofsubframe denial is for a particular uplink or downlink transmission. 9.The method of claim 1, in which transmitting the indication comprisestransmitting at least one of an interfering technology identifier,interfering direction information, and a traffic pattern indicator. 10.The method of claim 1, in which the measurement gap pattern creates agap pattern in at least one of downlink communications and uplinkcommunications.
 11. An apparatus for wireless communications at a userequipment (UE), comprising: a processor; a memory coupled with theprocessor; and instructions stored in the memory and operable, whenexecuted by the processor, to cause the apparatus: to identify acoexistence issue corresponding to a set of communication resources ofthe UE; to transmit an indication of the coexistence issue to a basestation; to receive a communication parameter for selectively schedulinga measurement gap pattern of the UE based on the transmitted indication;and to communicate with the base station according to the selectivelyscheduled measurement gap pattern to mitigate the coexistence issue. 12.The apparatus of claim 11, in which the measurement gap pattern createsa gap pattern in at least one of downlink communications and uplinkcommunications.
 13. The apparatus of claim 11, in which the instructionsto transmit the indication further cause the apparatus to transmit astatic indicator of a multi-radio capability of the UE, the staticindicator comprising a one-time indication of existence of radioresources in the UE.
 14. The apparatus of claim 11, in which theinstructions to transmit the indication further cause the apparatus totransmit a message indicating at least one of an enabled communicationresource and a disabled communication resource.
 15. The apparatus ofclaim 11, in which the instructions to transmit the indication furthercause the apparatus to transmit an indicator of a portion of bandwidthwithout coexistence issues.
 16. The apparatus of claim 11, in which theinstructions to transmit the indication further cause the apparatus totransmit an indicator of at least one of an interfering technologyidentifier, interfering direction information and a traffic patternindicator.
 17. The apparatus of claim 11, in which the instructions totransmit the indication further cause the apparatus to transmit anindicator of an uplink transmission or a downlink transmission denied bythe UE due to the coexistence issue.
 18. The apparatus of claim 11, inwhich the instructions to transmit the indication further cause theapparatus to transmit an indicator of a rate of subframe denial at theUE due to the coexistence issue.
 19. An apparatus for wirelesscommunications at a base station, comprising: a processor; a memorycoupled with the processor; and instructions stored in the memory andoperable, when executed by the processor, to cause the apparatus:receive, from a user equipment (UE), an indication of a coexistenceissue corresponding to a set of communication resources of the UE;determine a communication parameter for selectively scheduling ameasurement gap pattern of the UE based on the received indication; andassign the communication parameter to the UE to mitigate the coexistenceissue.
 20. The apparatus of claim 19, in which the measurement gappattern creates a gap pattern in at least one of downlink communicationsand uplink communications.
 21. The apparatus of claim 19, in which theinstructions to receive the indication further cause the apparatus toreceive a static indicator of a multi-radio capability of the UE thestatic indicator comprising a one-time indication of existence of radioresources in the UE.
 22. The apparatus of claim 19, in which theinstructions to receive the indication further cause the apparatus toreceive a message indicating at least one of an enabled communicationresource and a disabled communication resource.
 23. The apparatus ofclaim 19, in which the instructions to receive the indication furthercause the apparatus to receive an indicator of a portion of bandwidthwithout coexistence issues.
 24. The apparatus of claim 19, in which theinstructions to receive the indication further cause the apparatus toreceive an indicator of a rate of subframe denial at the UE due to thecoexistence issue.
 25. A method of wireless communication by a basestation, comprising: receiving, from a user equipment (UE), anindication of a coexistence issue corresponding to a set ofcommunication resources of the UE; determining a communication parameterfor selectively scheduling a measurement gap pattern of the UE based onthe received indication; and assigning the communication parameter tothe UE to mitigate the coexistence issue.
 26. The method of claim 22, inwhich receiving the indication comprises receiving a static indicationof a multi-radio capability of the UE, the static indication comprisinga one-time indication of existence of radio resources in the UE.
 27. Themethod of claim 22, in which receiving the indication comprisesreceiving a message indicating at least one of an enabled communicationresource and a disabled communication resource.
 28. The method of claim22, in which receiving the indication comprises receiving an indicatorof a portion of a bandwidth without coexistence issues.
 29. The methodof claim 22, in which receiving the indication comprises receiving anindicator of an uplink transmission or downlink transmission denied bythe UE due to the coexistence issue.
 30. The method of claim 22, inwhich the measurement gap pattern creates a gap pattern in at least oneof downlink communications and uplink communications.